Hadn't considered that. I have focused on kindlegen because that is backed by amazon to produce good results on kindle devices. And of course there is no way to test output on a Fire, they haven't been released yet. And this is for publication, not just for personal use.

If you hadn't considered using calibre to convert the file to mobi why did you post in the calibre - conversion forum?

It seems recently many folks have mistaken the calibre forums for a generic html help forum or a generic how-to create an ebook forum in xy or z formats. There is a whole section in the mobileread forums dedicated to answering these kinds of questions.